Description of problem:
I've been writing an experimental static analysis tool to detect bugs commonly occurring within C Python extension modules:
https://fedorahosted.org/gcc-python-plugin/http://gcc-python-plugin.readthedocs.org/en/latest/cpychecker.htmlhttp://fedoraproject.org/wiki/Features/StaticAnalysisOfPythonRefcounts
I ran the latest version of the tool (in git master; post 0.9) on
lunatic-python-1.0.1-0.6.20090917bzr.fc17.src.rpm, and it reports various errors.
You can see a list of errors here, triaged into categories (from most significant to least significant):
http://fedorapeople.org/~dmalcolm/gcc-python-plugin/2012-02-18/lunatic-python-1.0.1-0.6.20090917bzr.fc17/
I've manually reviewed the issues reported by the tool.
Within the category "Reference leaks" the 1 issues reported
src/pythoninlua.c:py_object_call:ob_refcnt of '*args' is 1 too high
appears to be a genuine bug: the "args" is tuple is allocated, populated, and passed to PyObject_CallObject(), but nothing seems to do a Py_DECREF() on it, hence the tuple of arguments becomes immortal for the rest of the lifetime of the process. If I'm reading this correctly, every call to py_object_call will leak memory.
There may of course be other bugs in my checker tool.
Hope this is helpful; let me know if you need help reading the logs that the tool generates - I know that it could use some improvement.
Version-Release number of selected component (if applicable):
lunatic-python-1.0.1-0.6.20090917bzr.fc17
gcc-python-plugin post-0.9 git 771455b3128b1323e80bdda53939d8d140a84c68 running the checker in an *f16* chroot

No, it just needs it once, I think, rather than nargs times: "args" is the whole tuple, which the code owns one reference to.
I think this code just needs a single extra Py_DECREF(args) at around line 137, like this:
value = PyObject_CallObject(obj->o, args);
+ Py_DECREF(args);
if (value) {